Manufacture and characterization of aa6061 aluminum alloy metal matrix composites with ceramic particulate reinforcement

Abstract

The work’s main objective was the manufacture of an AA6061 aluminum metal matrix composite reinforced with ceramics reinforcements of: aluminum oxide, silicon carbide, aluminum nitride and silicon nitride, through the powder metallurgy technique. The powders were subjected to high energy milling in a SPEX type vibrating mill. Thereafter, a cold uniaxial compactation was made and then the compacts were hot extruded. The powders were subjected to characterization using X-ray diffraction and laser diffraction granulometry. The extruded were characterized by scanning electron microscopy, energy dispersive spectroscopy and had their microhardness evaluated. The characteri-zation showed: the reinforcements’ addition in the matrix contributed to an acceleration of powders’ grinding; the reinforced samples had a higher microhardness than the unreinforced; it was observed that greater milling times and reinforcement’s addition increased the composites’ microhardness.